News & Views in 2019

Moving to more renewable energy generation will require more flexible electricity use. Now, research shows that flexibility products like time of use rates can hit some groups harder than others, with some vulnerable groups facing disproportionately negative financial and health impacts. However, the picture is by no means simple.

Developing high capacity yet stable cathodes is key to advancing Li-ion battery technologies. Now, a new metal oxide cathode that is rich in Li with a gradient in Li concentration is shown to be stable to O₂ release leading to long cycle life and high capacity.

Metal–organic frameworks are promising adsorbents for CO₂ capture from flue gas, but many perform poorly when exposed to flue gas containing water. Now, a computational screening approach identifies MOFs with preserved CO₂/N₂ selectivities in wet flue gas and experiments confirm their outstanding CO₂ capture performance.

Adoption of photovoltaic systems has been thought of in some countries as a choice influenced by political preferences. In the US, this polarization may be even stronger due to political polarization around climate change. Now, research shows that photovoltaic adopters can be found in both parties and they are politically active.

Energy transitions might require not only changes in fuel mix, but also consumption reduction. Using surveys of behaviour and basic human needs, new research estimates the minimum energy required for maintaining a decent living standard.

Obtaining simultaneously high power conversion efficiency and long-term stability in organic blend/quantum dot solar cells is considered a tough challenge. Now, realization of a hybrid architecture that exploits the addition of a small molecule brings researchers a step closer to overcoming it.

Capacity markets are meant to ensure adequate generation capacity to avoid electricity shortages without benefitting specific technologies. Now, research shows that by minimizing investment risks over operating risks, these markets favour fossil fuels over renewable energy unless other complementary instruments are introduced.

The performance of lithium–sulfur batteries is intimately tied to electrode porosity. Now, an in-depth investigation shows that optimizing the porosity enhances the achievable energy density of lithium–sulfur batteries.

In the development of Li metal solid-state batteries, understanding the mechanism that governs fundamental processes such as Li stripping and plating is pivotal. Now, researchers uncover a pressure dependence on Li stripping and higher pressures are suggested for faster discharging.

Coal power generation in China is among the major causes of the country’s heavily polluted air. Researchers now use comprehensive emissions monitoring data to show that many plants report compliance with new ultra-low emissions standards earlier than required, substantially reducing the pollution they emit.

Copper-doped cadmium telluride thin-film solar cells have high efficiency, but limited hole density and Cu diffusion allow little room for further improvements in device performance. Now, arsenic-doped cadmium telluride thin films show enhanced hole density and lower dopant diffusivity leading to 20.8%-efficient solar cells.

For the well informed, taking actions to curb energy consumption from household appliances is uncomplicated. Now, research shows that simple information provision interventions can correct consumer misperceptions of the energy consumed by common appliances, offering hope to the rest of us.

Large-scale electrolytic production of hydrogen from water using renewable energy will require solutions to issues that arise when using intermittent power, such as gas mixing and low efficiency. To this end, an electrolysis system is now described that decouples the gas generation reactions and uses thermal energy to drive oxygen evolution.

Electrochemically reducing CO₂ into value-added chemicals could contribute to CO₂ recycling while storing renewable energy. However, reaction products are typically mixed with additional solutes in the liquid electrolyte. Now, a cell that uses a solid electrolyte is shown to produce pure liquid fuel solutions from CO₂.

Ultrathin III–V solar cells are sought after for their relatively low cost and potential novel applications such as hot-carrier solar cells, but currently suffer from low power-conversion efficiency. Now, light-trapping nanostructures have been demonstrated to enable efficiency of 19.9% in a 205-nm-thick GaAs solar cell.

A conventional lithium-ion battery makes use of both an anode and a cathode. Now, a new design of batteries with no anodes in their initial state is shown to be promising for practical applications.

The optimization of building envelopes plays a substantial role in reducing global energy consumption and meeting energy and climate targets. Now, a dynamic photovoltaic building envelope has been demonstrated to improve building energy self-sufficiency, while adapting to changing weather conditions and occupant needs.

An unwelcome effect of rapid industrialization in China over the past 60 years has been the rise in air pollution. Researchers now estimate how the solar dimming caused by pollution reduced the potential for solar energy generation in China. However, reduction of pollution to 1960s levels can increase this potential significantly.

India has distributed subsidized liquefied petroleum gas (LPG) connections to the poor at a hitherto unseen pace. However, it has been unclear whether this successfully supports a shift away from solid fuel. Research now shows that connection subsidy alone is not enough to promote sustained LPG consumption among rural poor households.

Fossil fuels have long been considered cheap compared to other energy sources, such as solar or wind. Researchers now show that with easy-to-access fossil fuels running out, the more productive renewables may be approaching and even exceeding oil and gas in net energy generation in many cases.